For example, an electromagnetic relay mounted in a vehicle or the like includes a base and a box-like cover having an opening at the base side. A sealed space is formed by the base and the cover. In the sealed space, a coil wound around a coil bobbin, an iron core inserted into the coil bobbin, a yoke which forms a magnetic path together with the iron core, a contact portion performing a switching operation based on magnetization and demagnetization of the iron core, and the like are disposed.
The contact portion includes a movable contact connected to a movable contact terminal and a fixed contact connected to a fixed contact terminal. The movable contact terminal and the fixed contact terminal protrude outward through slits formed in the base. Further, the movable contact terminal and the fixed contact terminal are connected to an external load.
In the above configuration, the movable contact comes in contact with (ON) or is separated from (OFF) the fixed contact based on magnetization or demagnetization of the coil. According to the ON or OFF operation of the contacts, an electric current of an external power source (not shown) is supplied to the load or the supply of the electric current is interrupted (for example, see Patent Literature 1).
Further, in an electromagnetic relay mounted in, for example, a vehicle, a contact portion and a coil magnetizing or demagnetizing an iron core are adjacently arranged on a base. Similarly, in this case, a contact portion includes a movable contact connected to a movable contact terminal and a fixed contact connected to a fixed contact terminal. The movable contact comes into contact with or is separated from the fixed contact based on magnetization or demagnetization of the coil.
Specifically, the movable contact is arranged on one end side of a movable contact plate of a flat spring, and the other end side of the flat spring is supported by a yoke which forms a magnetic path together with the iron core. A base end of the movable contact terminal is also attached to the yoke. As described above, the movable contact is connected with the movable contact terminal via the movable contact plate and the yoke. Further, the movable contact and the fixed contact are arranged in the separated state.
In this state, when an electric current is applied to the coil, the movable contact is attracted to and comes into contact with the fixed contact due to electromagnetic force generated in the coil, the fixed contact terminal is electrically connected with the movable contact terminal, and the electric current flows through the fixed contact terminal and the movable contact terminal. Meanwhile, when supply of the electric current to the coil is cut off, the movable contact is separated from the fixed contact according to an elastic operation of the flat spring in which the movable contact is arranged, and supply of the electric current to the fixed contact terminal and the movable contact terminal is stopped (for example, see Patent Literature 1).